Fuse-plug.



H. T. PAISTE.

FUSE PLUG.

' APPLICATION 11.31) DEC. 6, 1911.

j UNITED STATES PATENT OFFICE.

HENRY 'r. PAISTE, on PHILADELPHIA; PENNSYLVANIA, ASSIGNOR TO n. T. PAISTE COMPANY, or PHILADELPHIA, PENNSYLVANIA, 'A CORPORATION or PENNsW- VANIA.

Fuss-PLUG.

T 0 all whom it may concern 13s it known that I, HENRY T. Plnsrn, a citizen of the United States, residing in Philadelphia, Pennsylvania, have invented fuse burns out.-

Another object of the invention is to provide a fuse plug consisting of a body portion carrying one of the contacts and the cover, and including a capsule of relatively 'inexpensive construction carrying the fuse )lu' in which those elements of a com mintively costly nature shall be included in one part, while thefuse proper shall be carried upon the relatively inexpensive second part which may be discarded without serious loss when the'fuse is burned out, the other por-' tion being repeatedly used with new capsules. These objects and other advantageous ends I secure as hereinafter set forth, reference being had to theaccompanying drawings, in which Figures 1 and2, are'perspective Views of the body and capsule of afuse constructed according to my invention; Figs. 3 and 4,; are respectively vertical sections of the body and capsule shown in 1 and 2; and,

Fig. 5, is a plan of the bod-y portion of the fuse structure prior to the mounting thereon of the cap or cover, showing the arrangement of the gas passages. i

fIn the above drawings the body 1 of the fuse is illustrated as consisting of .a porce- Specification of Letters Patent.

Application filed December 6, 1911.

Patented Nov. 11, 1913.

Serial No. 664,157.

lain or other insulating supporting structure of annular form, the opening through which is beveled or outwardly flared at oiie end. The opposite end ofthe opening is permanently closed by a transparent sheet 2 of mica or-othersuitable material held in place by the flange of a metal ring spun or turned over a shoulder of the supporting structure 1 so as to be rigidly held thereto.

A metal shell 4; is likewise rigidly mounted in the hole in the structure 1 and for this central opening or hole at that end adjacent.

the cover 2 and designed for the reception of lugs or extensions 8 of the part 5 of the shell whereby the latter is rigidly held to the said structure. The outer portion 9 of the shell 4 is provided with threads and is of such a diameter as to screw into a standard fuse plug receptacle. i

The fuse proper is carried by a capsule 10 of porcelain or other insulating material having two portions 11 and 12 of cylindrical form joined by a part 13 of conical shape. The capsule is hollow for practically its entire length as indicated at 14, and has centrally mounted on that end adjacent the large diameter portion 12 a contact or terminal 15 in the shape of a dislcproyidcd with lugs 16 extending into the hollow 14. One or both of these lugs may be turned over or spread out so as to hold the disk 15 rigidly and permanently in place. Adjacent the open or small diameter-end of the cap sule I provide in the wall thereof a relatively narrow opening 17 which is flared outwardly from the point where it opens into the recess or hollow 14:. At a point on the outer surface of the capsule adjacent the line of junction of the parts 12 and 13 thereof, I provide "a small undercut recess 18 for the reception After the fuse has been put in place I preferably fill the openings 17 and 18 with a suitable cement. Under conditions of use the capsule is loosely placed Within the shell in the position indicated in dotted lines in Fig. 3, and the threaded portion 9 of said shell is screwed into a socket or receptacle of the ordinary type, until the disk 15- engages the central contact thereof, it being noted that the open end of said capsule projects beyond the extensions or lugs 8. If the electric circuit is otherwise complete, current is now free to flow from the disk 15 to the fuse l9 and thence from the inclined or contact portion of said fuse to the shell 9 and the corresponding shell of the receptacle engaged thereby; it being noted that the act of screwing the shell 9 into the receptacle causes the capsule to be pressed into the conical part of said shell, thereby insuring good electrical contact between that part of the fuse 19 which lies on the inclined surface 13 of the capsule and the inner conical surface of said shell.

t The condition of the fuse may conveniently be inspected through the transparent cover plate in the well known manner, since the open end of the capsule is immediately adjacent thereto, and when the fuse is blown or broken the capsule, being of relatively inexpensive construction, may be discarded and replaced by another having a perfect fuse. The body of the fuse structure with its relatively expensive pressed shell 4 and cap 3 is thus available for repeated use.

It is noted that I preferabl ,form the opening 17 with its outer end fared in the manner illustrated in Fig. 4, to facilitate the passage through it of the end of the fuse 19, which has previously been soldered to one of the lugs on the disk 15, for the free end of said fuse, after being introduced through the hollow 14, is bent over and threaded through the said opening 17 from the inside thereof. Thereafter the end of the fuse is turned down and hooked in the opening 18 where it is retained even in the absence of cement.

In order to permit escape of the gases formed as a consequence of "the blowing of the fuse 19 and at the same time render impossible the escape of molten metal or of incandescent gases I form a series of notches 21 in the periphery of the porcelain body 1 and connect these with the radial recesses 7 by channels 22 concentric with the center line of the plug. lVith such arrangement of tortuous passages any gases formed in the interior of the capsule will be so far cooled in passing through the recesses 7, channels 22, and the notches 21 that there is no danger from fire nor any possibility of damage from molten fuse metal.

I claim: l 1. The combination 1n a fuse plug, of a hollow body; a terminal and a structure having a contact surface on said body; with a fuse capsule of insulating material removably mounted in the body and having an inclined surface formed to co-act with the contact surface on the said body; a

terminal on the capsule; and a fuse permanently connected to the terminal and extending over the inclined surface of the capsule in position to engage the contact surface of the body.

2. The combination in a fuse plug of a hollow body; a cap thereon; a threaded shell extending into the body and having an inclined surface; a capsule loosely mounted in the shell and having a terminal with a fuse permanently connected to the terminal and having a portion on the outer surface of the capsule in position to engage the inclined surface of the shell.

3. The combinationin a fuse plug of a hollow body having a terminal and a'contact surface; a fuse capsule of insulating material loosely mounted in the body and having an inclined surface; a terminal and a conductor carried by the capsule and permanently connected together; said conductor extending over the inclined portion of the capsule in position to engage the contact surface of the body and including a part designed to fuse at a predetermined temperature.

4. As a new article of manufacture, a fuse capsule consisting of a hollow body of insulating material open at one end and having a single exterior contact at the other end; with a conductor including a fuse pern'ianentlyconnected to the end contact and extending through the hollow portion of the capsule, said fuse passin through the wall of the capsule at a polnt spaced away from the open end and from the outside surface of said capsule to the side portion thereof.

5. As a new article of manufacture, a fuse capsule consisting of a hollow body of insulating material in the form of two cylindrical sections and an inclined section connecting said other sections; a terminaLcontact at one end of the capsule; with a fuse connected to said contact extending longitudinally through the capsule, through an opening in the side thereof and over a portion of the inclined exterior surface of the capsule.

6. As a new article of manufacture, a fuse capsule consisting of a body of insulating material having an'inclined exterior surface and an under-cut recess; a contact mounted on the body; and a fuse connected to said contact extending through the body, over the inclined portion of the exterior surface thereof, and hooked in said under-cut recess. a

7. As a new article of manufacture, a fuse capsule-consisting of a ,body of insulating material in the form. of an elongated tube closed at one end; a terminal contact at'said closed end of the tube; there being an opening through tube at the opposite end thereof with a fuse permanently connected to said contact passing therefromthrough said opening and extending over the outside tube in position to serve as a-contact.

8. As a new article of manufacture, a fuse capsule consistin'g'of a body of insulating material in the form of an elongated tube closed at one end; a terminal contact at said closed end of the tube; there being "an openin through the Wall of the tube at the opposite end thereof formed with its sides outwardly flared; with a fuse connected to said contact, passed through the hollow of the body and the-opening in the side wallthereof and then extended over the exterior surface of the body.

9, As a new article of manufacture afuse plug body consisting of a hollow supporting structure of insulating material; and an internally threaded shell mounted in said body and projecting to form a terminal;

said shell having a portion of its interior surface inclined to its longitudinal axis to torm a contact, and engaging a correspond- Copies of this patent may be obtained for the wall of the surface of the ingly inclined supporting surface within the insulating structure.

.10. As a new article of manufacture, a {use plug body consisting of an outer supporting structure of insulating material provided with a plurality of radiating recesses adjacent one face thereof and a threaded metallic shell having an internal contact portion and a cylindrical portion connected thereto, extending into said supporting structure; said cylindrical portion of the shell being provided with radially extending arms fitting the recesses of said supporting structure.

- 11.'The combination in a fuse plug of a hollow body of insulating material; a metallic shell fitting therein and provided with projecting portions entering recesses in the with a fuse capsule removably exten ing into the shell; the inner end of said capsule being open and projecting into said body beyond the said projecting portions. In testimony whereof, I have signed my name to this specification; in the presence of two subscribing witnesses.

HENRY T. PAISTE.

Witnesses CHARLES W. GRAHAM, Jos. H. KLEIN.

five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

